Event Notification Report for November 23, 2002
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
11/22/2002 - 11/23/2002
EVENT NUMBERS
39401
Power Reactor
Event Number: 39401
Facility: SURRY
Region: 2 State: VA
Unit: [] [2] []
RX Type: [1] W-3-LP,[2] W-3-LP
NRC Notified By: ALISON MACKELLAR
HQ OPS Officer: ERIC THOMAS
Region: 2 State: VA
Unit: [] [2] []
RX Type: [1] W-3-LP,[2] W-3-LP
NRC Notified By: ALISON MACKELLAR
HQ OPS Officer: ERIC THOMAS
Notification Date: 11/23/2002
Notification Time: 07:37 [ET]
Event Date: 11/23/2002
Event Time: 03:32 [EST]
Last Update Date: 11/23/2002
Notification Time: 07:37 [ET]
Event Date: 11/23/2002
Event Time: 03:32 [EST]
Last Update Date: 11/23/2002
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(2)(iv)(B) - RPS ACTUATION - CRITICAL 50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION
10 CFR Section:
50.72(b)(2)(iv)(B) - RPS ACTUATION - CRITICAL 50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION
Person (Organization):
DAVID AYRES (R2)
DAVID AYRES (R2)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 2 | A/R | Y | 85 | Power Operation | 0 | Hot Shutdown |
AUTOMATIC REACTOR TRIP DUE TO LOW-LOW STEAM GENERATOR LEVEL
"At 0332 hours, with Surry Power Station Unit 2 at 85% reactor power, a low low S/G level signal was received which resulted in an automatic reactor trip. Immediately prior to the trip, the Turbine Stop and Governor Valves were being manipulated for a scheduled Governor Valve Freedom Test. While closing Turbine Governor Valve #3 the Turbine Valve Limiter failed to zero closing all four governor valves. This led to the automatic reactor trip.
"IRPI indications for six control rods indicated between 11 and 20 steps following the trip. [Unit 2 was] borated as necessary to ensure adequate shutdown margin. All other control rods fully inserted into the core as designed. The shutdown margin for Unit 2 was determined to be satisfactory. Auxiliary feedwater automatically initiated [ESFAS] as designed on low low steam generator level. All three Main Steam Trip Valves were manually closed due to inability to verify full closed indication on #1 Turbine Stop Valve. Primary RCS temperature decreased to approximately 547 degrees following the reactor trip and is currently stable on the Secondary Power Operated Relief Valves.
"No primary safety or power operated relief valves were actuated during the event. No indication of primary to secondary leakage exists, therefore no adverse radiological consequences resulted from this event.
"All electrical busses transferred properly following the trip and all emergency diesel generators are operable. There were no radiation releases due to this event, nor were there any personnel injuries or contamination events. The cause of the event is being investigated.
"Unit 2 is currently at Hot Shutdown with RCS temperature being maintained at approximately 547 degrees.
"Unit 1 was not affected by this event and remains stable at 100% power operations.
"This event is being reported in accordance with 10CFR50.72(b)(2)(iv)(b)."
The Resident Inspector was notified of this event.
"At 0332 hours, with Surry Power Station Unit 2 at 85% reactor power, a low low S/G level signal was received which resulted in an automatic reactor trip. Immediately prior to the trip, the Turbine Stop and Governor Valves were being manipulated for a scheduled Governor Valve Freedom Test. While closing Turbine Governor Valve #3 the Turbine Valve Limiter failed to zero closing all four governor valves. This led to the automatic reactor trip.
"IRPI indications for six control rods indicated between 11 and 20 steps following the trip. [Unit 2 was] borated as necessary to ensure adequate shutdown margin. All other control rods fully inserted into the core as designed. The shutdown margin for Unit 2 was determined to be satisfactory. Auxiliary feedwater automatically initiated [ESFAS] as designed on low low steam generator level. All three Main Steam Trip Valves were manually closed due to inability to verify full closed indication on #1 Turbine Stop Valve. Primary RCS temperature decreased to approximately 547 degrees following the reactor trip and is currently stable on the Secondary Power Operated Relief Valves.
"No primary safety or power operated relief valves were actuated during the event. No indication of primary to secondary leakage exists, therefore no adverse radiological consequences resulted from this event.
"All electrical busses transferred properly following the trip and all emergency diesel generators are operable. There were no radiation releases due to this event, nor were there any personnel injuries or contamination events. The cause of the event is being investigated.
"Unit 2 is currently at Hot Shutdown with RCS temperature being maintained at approximately 547 degrees.
"Unit 1 was not affected by this event and remains stable at 100% power operations.
"This event is being reported in accordance with 10CFR50.72(b)(2)(iv)(b)."
The Resident Inspector was notified of this event.